The US Supreme Court Tuesday ruled that a drug dog's sniff of a residence's front door is a search under the meaning of the Fourth Amendment and that police must therefore obtain a search warrant before unleashing the hounds. The case was Florida v. Jardines.
"A police officer not armed with a warrant may approach a home and knock, precisely because that is no more than any private citizen might do," Scalia reasoned. "But introducing a trained police dog to explore the area around the home in hopes of discovering incriminating evidence is something else. There is no customary invitation to do that."
The case arose when a Miami police detective investigating an anonymous tip about a marijuana growing operation had his drug dog sniff the base of the home's front door. The dog "alerted" on the scent of marijuana, and only then did police obtain a warrant to search the home. They then found 25 pounds of pot inside and arrested Jardines.
Jardines was charged with trafficking in marijuana, but the trial court approved his motion to suppress the evidence on the basis that the drug dog sniff amounted to a warrantless search. The Florida Supreme Court upheld the trial court, and the state of Florida then appealed to the Supreme Court.
The 5-4 decision sundered the typical liberal-conservative split on the court. Joining the conservative Scalia in the majority was conservative Justice Clarence Thomas, along with liberal justices Ruth Bader Ginsburg, Sonia Sotomayor, and Elena Kagan.
In a concurring opinion joined by Ginsburg and Sotomayor, Kagan went further than Scalia, arguing that the drug dog sniff violated Jardines' reasonable expectation of privacy.
In a dissenting opinion, Justice Samuel Alito, joined by Chief Justice John Roberts, Justice Anthony Kennedy, and Justice Stephen Breyer, rejected the privacy argument and opined that the search should have been upheld.
"A reasonable person understands that odors emanating from a house may be detected from locations that are open to the public," Alito wrote. "A reasonable person will not count on the strength of those odors remaining within the range that, while detectable by a dog, cannot be smelled by a human."
But that was the minority opinion. As of now, if the police want to use a drug dog to sniff a home's front door, they need to get a warrant.